Core-peeling device for foundries



R. BRUNE C RE FEELING DEVICE onrounnnms Nov. 19, 1929.

Filed Oct. 25. 1926 Zudb l/Zr un if Patented Nov. 19, 1929 UNITED STATES PATENT orrica RUDOLF BBUNE, OF DOBTMUND, GE

GORE-FEELING DEVICE FOR FOUNDBIES A Application filed October 23, 1926, Serial No. 148,722, and in Germany October 29, 1925.

This invention hasreference to means for the trimming, peeling or shelling of sand cores for casting purposes, and it is one of the important objectsof my invention, to devise means of facilitating this operation and to secure exact shapes and reliable results irrespective of the shape of the cores to be treated. The means heretofore employed for manufacturing foundry cores do not admit of the manufacture of cores of all required sizes, it being particularly difficult to obtain comparatively thick and long .cores and cores of varying cross sections with the means suggested by the previous art. It is however a 'p'oint of great importance in the case of the operation of foundries according to modern methods to be able to obtain not only relatively elongated, but also comparatively thick cores, and cores of three-cornered, four-cornered, six-cornered, oval or other cross sectional shapes, and this object is realized by the means set forth in the invention to be described hereinafter.

The invention is shown by way of exemplification in a preferred embodiment in Figure 1 of the drawing in vertical section and in Figure 2 in plan view. Figures 3 and 4 are illustrations of a peeling or trimming device for a hexagonal core, shown respectively in vertical section and in plan view. Figures 5 and 6 are representations of details showing respectively cutting knives with substantially square and rectangular shapes and with .rounded edges.

Upon the foundation or foot 1 which may be hollowed out or provided with holes with a view of reduction of weight the standards or connecting bolts 2 are disposed upon which the sand chest or bin 3 is mounted which latalso acts'as a lifting and cam-bar. At its vice in a casing 18 wh ter at its front side is provided with a re'-- lower portion the bar 13 is guided in the hearing 14 and its upper portionis rovided with a piston or plunger 15 upon wl ich a wooden 7 plate or the like 16 is mounted. This plate is intended to prevent injuring the peeling or trimming knife 17 by the iron piston orplunger 15 and to entirely force the core through the trimming or peeling knife.- The said cutting, trimming or peellng instrumentality 17 is disposed in the up er part of the de- 00' loll is mounted upon the conical core-tube 22 by bayonet joint or the like. The oblong discs 20 which are fastened to the trimming or peeling instrumentality 18 by means of the small screws 19 admit of the ready loosenin of the peeling or trimming knives and o the replacing thereof by a smaller or larger or differently shaped knife in accordance with the core to be produced. The core-tube or sleeve 22 may likewise be connected by bayonet-joint to the foundation or foot 1 and at its upper portion to the plate 23, which latter may Joe secured to the plate of the sand box 3'together. with the peeling or trimming instrumentality by a bayonet joint or the like 24. Instead of bayonet joint screw-threaded connection may be employed. The core sleeve 22 is of somewhat reduced diameter at its lower end so as to be flaring upwards. This feature is of importance, inasmuchas by this means the friction of the core-material against the walls which is particularly great in the case of sand and similar core-material is reduced, adhesion to the walls is prevented and the integ rity of the core is preserved. The diameter of the plunger 15, 16 which is not a compressing, but merely a supporting plunger corresponds to the narrower part of the containing tube 22, so as to eliminate friction and jerking movement. In Figure 1 of the drawing the plunger members 15, 16 are indicated in dotted lines in their lowermost position, and

in full lines in their raised operative position in which the plunger-members 15, 16 are out of contact with the walls of the container.

- The way of the chain 9 is indicated in broken lines.

The trimming or peeling knife 17 may as- I sume different polygonal shapes; as shown in 10 Figures 3 and' l at 25,it mag be substantially hexagonal; or it may be su tantially square or four-cornered, as shown at 26 in Flgure 5; or it may be of oblong rectangular shape 27 according to Figure 6. But it should be understood that by correspondingly chang ng the configuration of the peeling or trimming knife any desired suitable shape of core may be obtained.

In order to provide a shoulder or a stem on the cores, which is often required, the

trimming or peeling instrumentality 18 may shapes of the cores the corresponding knives 17 and the corresponding core sleeves 22 are inserted. For the reception of the rack bar or lifting bar 13 a tube 32 is provided below the foot in the ground.

After the rack bar 13 has been fully lowered by rotating the crank handle and the sprocket wheel 8, the core tube or sleeve 22 is filled with the foundry sand which is packed and pounded by hand; then the rack bar 13 with the piston 15 and the wooden plate 16 are raised, until the core has been trimmed off and peeled by the knife 17. The laterally dropping off core sand may be pushed into. the sand box 3 and may be used for the buildingof the next core- Inasmuch as the core-material, particularly sand or the like, must be protected and pre served against any deformation, bending, expansion, change of volume, and undue tension, it is obvious that the various devices employed for the forcing of astream of clay or similar plastic material through a die member cannot be employed for the purposes of this invention, nor for the surface-treatment of foundry-cores generally, inasmuch as they all impose a very injurious strain on the-material, and put it under a rather heavy compressing pressure, aside from the additional very serious drawback that in most of the devices for the treatment of a stream of clay or other plastic material this material is fed horizontally either insufliciently supported, and thereby subject to friction, or even not supported at all, so as to be. open to bending and deformation. Of course, all such difficulties militate against the purpose of exactness, precision andunchangeability which are conditions of paramount imporly widening tubular member, a plunger axially movable in said member and corresponding to the smaller diameter thereof, and trimming means, marginally disposed at the wider end of said member.

2. Trimming and smoothing device for foundry cores comprising in combination, a substantially vertically disposed, upwardly gently widening tubular containing member, a supporting plunger corresponding to the smaller diameter of said member and mov-' able axially thereof, and adapted to support a foundry-core, and trimming means, marginally disposed at the wider part of said memher, and engageable with the foundry-core.

3. Trimming and smoothing device for foundry-cores comprising in combination, a base, a substantially v trough-shaped head, spacedly superimposed with relation thereto, a substantially vertically disposed, upwardly widening tubular containing member intermediate the head and the base and detachably secured to them, a supporting plunger in said member corresponding to the smaller diameter thereof, and axially movable. therein, and adapted to removably support a foundry-core, marginally arranged trimming knives at the wider part of said member, en-

gageable with the foundry core, and opera'ting means for the plunger.

4. Trimming and smoothing device for foundry-cores comprising in combination, a substantially vertically disposed, upwardly widening tubular containing member, a plunger axially movable in said member and corresponding to the diameter of the narrower part thereof and adapted to support a re movable foundry-core, marginally disposed trimming knives for said core at the wider part of said tubular member, and additional rotatable trimming ;means for said core mounted at said wider part.

5. Trimming and smoothing device for foundry-cores comprising in combination, a substantially vertically disposed, upwardly widening tubular containing member, a plunger, axially movable in said member and corresponding to the diameter of the narrower part thereof, and adapted to removably support a foundry-core, marginally disposed trimming knives at the wider part of the tubular member and engageable with the core, ad

women ditional movable knives at said wider part engageable with the core out of the plane 0 the trimming knives.

6. Trimming and foundry-cores comprising in combination, a substantially vertically disposed,'upwardly Widening tubular containing" member, a

plunger axially movable in said member and smoothing device for- 

